Air circulation control



June 10, 1952 A. G. JANOS 2,600,297

AIR CIRCULATION-CONTROL Filea May 25. 1949 Fig.1. 2

IfiVentor: 32 Alfred G. Ja nos,

33 His Attorney.

Patented June 10, 1952 AIR CIRCULATION CONTROL Alfred G. Janos, Erie, Pa., assignor to General Electric Company, a corporation of New York Application May 25, 1949, Serial No. 95,191

4 Claims.

My invention relates to refrigerators and more particularly to arrangements for controlling air circulation within refrigerator cabinets.

It is an object of my invention to provide an improved arrangement for controlling air circulation within a refrigerator cabinet.

It is a further object of my invention to provide an improved arrangement for controlling air circulation in a, refrigerator cabinet wherein circulation of air is reduced when the refrigerating apparatus is not operating.

Further objects and advantages of my invention will become apparent as the following description proceeds, and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to to forming part of this specification.

In carrying out the objects of my invention a damper is provided for controlling the circulation of air through a passage within a refrigerator cabinet. The position of this damper is controlled by a solenoid energized in such a manner that the damper is open when the condensing unit is operating and closed when the condensing unit is not operating.

For a better understanding of my invention reference may be had to the accompanying drawing in which Fig. 1 is a front elevation view of a portion of a refrigerator cabinet incorporating my invention; Fig. 2 is a sectional side elevation view of the portion of a refrigerator cabinet; Fig. 3 is a schematic circuit diagram; Fig. 4 shows a modified form of my invention; and Fig. 5 is a schematic circuit diagram applicable to the form shown in Fig. 4.

Referring now to Figs. 1 and 2, there is shown a portion of a refrigerator cabinet I having a door 2 hinged thereto. The cabinet I includes an outer wall or shell 3 and a spaced inner wall or liner 4. The space between the inner and outer walls is filled with a suitable heat-insulating material 5. A breaker strip 6 is provided for closing the space between the inner and outer walls adjacent the door opening of the cabinet.

The liner 4 is shaped to define a food storage compartment 7 within the cabinet. In order to refrigerate this compartment an evaporator or cooling unit 8 is provided. This evaporator is positioned near the top of the food storage compartment l and is supported from the liner 4 by suitable brackets 9. The cooling unit 8 may be refrigerated by circulating vaporizable refrigerant through the evaporator by a suitable condensing unit (not shown) in the conventional manner. Of course, the invention is equally applicable to apparatus wherein a liquid refrigerant is circulated through the cooling unit by any suitable liquid-circulating apparatus. The evaporator 8 is shaped to provide a chamber for storing frozen food therein, and this chamber is closed by a door 10 hinged at H to the evaporator. A trough [2 extends across the front of the cabinet for catching drip from the door of the evaporator.

The air within the food storage compartment 7 is cooled as a result of natural circulation of the air over the evaporator 8. For example, the air may rise along the front portion of the cabinet, circulate rearwardly over the evaporator, and then descend in the rearward portion of the cabinet. To control this circulation of air a bafile and damper arrangement is provided. The baffle includes a drip tray l3 which is supported on suitable guides one of which is shown at M. A conventional receptacle I5 is also shown mounted on suitable guides, one of which is shown at [6, but this receptacle may be omitted, if desired, with no effect on the operation of the apparatus included in my invention. The drip tray [3 extends across the width of the food storage compartment 1, and the drip tray is made imperforate so that air cannot pass through the tray. Since the baille extends the full width of the food storage compartment air may pass between the lower portion of the food storage compartment and the cooling unit 8 only adjacent the front and the back of the ballle. As best shown in Fig. 2 the forward edge of the bafiie is spaced from the door 2 so as to provide a passage H for air. The rear edge of the bafile is spaced from the back wall l8 of the liner 4, providing a passage [9 for the circulation of air from the region of the evaporator 8 to the lower part of the food storage compartment.

To control the circulation of air through the passage l9, a damper 26 is provided. The damper 20 is hinged at 2| to a bracket 22 which is secured by screws or other suitable fastening devices to the liner 4, one such screw being indicated at 23. The baflle further includes a horizontally extending bracket 24 which is secured in any suitable manner, as by welding, to a support 25, and the forward end of the damper 28 is adapted to engage the bracket 24. A lip 26 of the bracket 26 extends over the rear edge of the drip tray. It will be apparent that, if desired, the bracket 24 could be omitted and the damper 20 could be arranged to engage directly the rear edge of the drip tray [3. However, since the position of the drip tray [3 may vary from time to time it is preferable to utilize a bafile which includes not only the drip tray I3 but also the horizontally extending bracket 24. Moreover, although a drip tray has been shown as constituting the major portion of the battle, any imperforate structure disposed generally horizontally beneath the evaporator could be employed in lieu of the drip tray.

The damper 20 is adapted to occupy one position, as illustrated in Fig. 2, wherein the damper closes the passage 19 and reduces or blocks the circulation of air within the food storage compartment. The damper is adapted to occupy a second and substantially vertical position adjacent the rear wall H! of the liner 4 to allow circulation of air through the passage I9. In order to shift the damper to this second position a solenoid 2'? is provided, and the solenoid is mounted by screws 28, or other suitable fastening devices, on the bracket 22. An armature 29, which is controlled by the solenoid 21, is connected by a hinged link 36 to the forward edge of the damper 2!]. When the solenoid is energized, the armature 20 is attracted, moving upwardly to the right. and, through the link 30,'carrying the damper 20 to the second position generally adjacent the rear wall T8 of the liner 4.

In order to control'the energiz'ation'of the solenoid and, hence, the position of the damper 20, a circuit shown in Fig. 3 is provided. This circuit is arranged so that the damper occupies its closed position when theco'ndensing unit is idle and its open position whenfth'e condensing unit is operating. Referring to Fig. 3, power is supplied to the "solenoid 27 and to the motor of a condensing unit indicated generally at 31 from power lines 32, 33. The starting and stopping of the condensing unit is controlled in a conventional manner by "a temperature-responsive bulb 34 which is positioned adjacent the evaporator 8. The bulb 34 isconnectedbya tube 35to a'bellows 36. The expansionand contraction of the bellows 36 under the influence of 'thebulb 34 moves a toggle'switch 37 to th'e'clos'ed'and open'positions respectively to control "the supply of power to the condensing unit 3!. In the closed position the'cont'act arm of the toggle switch '31 engages a contact '31; in theopen'position the movement of the "contact arm is limited 'b'ya stop 31". In order to energizethesolenoid concurrently with the supplyingof pc'werto thec'ondensing unit 31,

the solenoid 27 'is "connected in parallel with the condensing unit 3 l'by'm'eans of conductors 38 and 39.

It'canbe seen,'therercre, that wh'enthe' evapor'atbr reaches a predetermined maximum temperaturethe switch 3'l is closed to start operation of 'thecondns'in'g'imit 1-H for supplying refrigerant tothe evaporator '8. At thes'aine time the switch 31 "ccmpietes a circuit to'riergi'ze the solenoid 2?. The solenoid attracts the armature '29 to opn'theda'mper 20 permitting air circulationthrough the passage 1'9. Conversely, when the'p'redetermined minimum temperature is reached the contractionof the bellows causes the switch 31 to open concurrently the power circuit to the condensing unit '3l and to'the solenoid 21. Upon deenergiza-tion' ofthe'solenoid the damper 20 falls'by gra'vity to the position shown in Fig. 2,'blocking or reducing the'circulation of air through the passage I9. Accordingly, by my arrangementthe damperzfl is'opened to permit circulation of airwithin the food storage compartment and over the "evaporator whenever power is supplied to "the condensing unit for the operation thereof. Conversely, the solenoid is deenergized formo'ving the damper to its closed position whenever-the circuit to the condensing unit is interrupted and -the condensing unit'is idle. In an ambient temperature of 60 F., for example, the condensing unit would operate only a small portion of the time and, hence, the damper would remain closed a large portion of the time restricting the air circulation within the compartment. In an ambient temperature of R, for example, the condensing unit would operate a much larger portion of the time and, accordingly, the damper would be maintained in its open position a much larger portion of the time permitting increased circulation of air. Since a smaller amount of air circulation is necessary in a room having a temperature of 60 F. than in a room having a temperature of 100 F. in order to adequately refrigerate food stored in the compartr'nent I, it can be seen that the arrangement described operates in accordance with the general refrigeration requirements.

In Figs. 4 and 5 there is shown a modified form of my invention in which the damper occupies its open position when the solenoid is deenergized and is moved to its closed position when the solenoid is energized. The same numerals have been applied to corresponding parts in Figs. 4 and 5 and in Figs. 1, 2, and 3. Referring now to Fig. 4, a damper '20 'is'pivotally mounted on'the back wall 18 of the liner 4, as indicated at 40. The damper is arranged to move between the open position, indicated by solid lines in Fig. 4, and the closed position, indicated by dotted lines in Fig. 4, wherein the forward edge M of the damper engages the'bracket portion 24 of the baiiie. The solenoid 2''! 'is provided for actuatingth'e'damper 26 between its open and closed positions. The solenoid is fastened by screws 28 or other fastening devices to a bracket '22. The 'bracke'tfl "is supported on the liner 4 by screws or'other suitable fastening devices-one such screw *bein'g'indicated at 23. The armature 2-9 is connected to the damper by the link '30, oneend of which is hinged to the armature 29 and the other end of which'is hinged to the damper 20'.

The energization of the solenoid 2T and'of the condensing unit 31 is controlled, as in the form previously described, by the temperature responsive bulb 34. This bulb is connected by a tube 3'5 to the'bellows "36. The expansionand contraction of the'bellows controls the position of 'a't'oggle switch 31. In the form'previously described the switch "arm concurrently opened and closed the circuits of the condensing unit'and'of 'th'e'solenoid. In the present form the switch '31 'is arranged so that it alternatively closes a circuit through the solenoid?! by'en'gagingthe contact 42 or closes a circuit through the condensing unit 3! by engaging a contact 43. I

The operationof the modified form 'sho'wnin Figs. '4 and 5 is as follows. When the temperature of the cooling unit or evaporator'lireaches a predetermined maximum, the switch '31 "is moved by expansion of the bellows 351:0 the 'position shown in Fig.5 wherein a circuit is closed from the power lines 32, '33 through the condens'ing unit 3!. At the sam'etirne the contact arm of the switch 3'ldisenga'ges fromthe contact ll breaking the circuit from the power-lines 32, 33 through the solenoid "'27. Upon the "deenergization of the solenoid the armature 2? falls by gravity to the p'ositio'n shown in Fig. "4 and the damper 20 ismoved to the 'solid'line' position illustrated in Fig.4, openingthe passage 49 and allowing increasedair circulationw'ithin the cabinet. Whenthe temperature oftheeva'porator'tireaches a predetermined minimum the resultant contraction of 'the bellows shifts 'the contact arm of the switch 31 out of engagement with the "contact "43 "and "into engagement with the contact"4'2. 'This concurrently interrupts the circuit't'o thecondehsing'unit 3| and closes the circuit'to the'solehoid "27. When thes'olen'oid is energi'ze'dthe armature 29 is'moved'upwardly to the right, thereby, through the link 30, shift-= ing the damper 2G to the closed position indicated by the dotted lines in Fig. 4.

It can be seen, therefore, that, as in the form previously described, the damper is shifted to the open position concurrently with the starting of operation of the condensing unit and the damper is moved to its closed position concurrently with the stopping of the condensing unit. Thus, an increased circulation of air is provided in the cabinet during the time when the condensing unit is operating and a decreased circulation of air is provided when the condensing unit 3! is not operating.

While I have shown and described specific em= bodiments of my invention, I do not desire my invention to be limited to the particular constructions shown and described, and I intend by the appended claims to cover all modifications within the spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In a refrigerator including refrigerant-circulating means, a food storage compartment and a cooling unit, a baffle within the food storage compartment providing a passage for air circulating within said compartment and over the cooling unit, a damper for controlling circulation of air through said passage, a solenoid for controlling said damper, and a single means dependent on the temperature of said cooling unit for starting and stopping said refrigerant-circulating means to maintain a predetermined range of temperature of said cooling unit during normal operation, said single temperature-dependent means actuating said solenoid to open said damper each time the refrigerant-circulating means is started whereby said damper is open at all times that said refrigerant-circulating means is operating.

2. In a refrigerator including refrigerant-circulating means, a food storage compartment and a cooling unit, a baflle within the food storage compartment providing a passage for air circulation within said compartment and over the cooling unit, a damper for controlling circulation of air through said passage, a solenoid for controlling the position of said damper, and a single means dependent on the temperature of a said cooling unit for starting and stopping said refrigerant-circulating means to maintain a predetermined range of temperature of said cooling unit during normal operation, said single temperature-dependent means actuating said solenoid to move said damper to its open position for increasing air circulation each time the refrigerant-circulating means is started whereby said damper occupies its open position at all times that said refrigerant-circulating means is operating, said single temperature-dependent means actuating said solenoid to move said damper to its closed position for decreasing air circulation each time said refrigerant-circulating means is stopped whereby said damper occupies its closed position at all times that said refrigerant-circulating means is idle.

3. In a refrigerator including a cooling unit and refrigerant-circulating means, means defining a food storage compartment, the cooling unit being disposed in the upper portion of said compartment, a bafile spaced from the bottom of said cooling unit and extending across the width of said compartment, said baflle extending substantially the entire depth of said compartment and being spaced from the back of said compartment to provide a passage for air circulating within said compartment and over said cooling unit, a damper disposed within said passage for controlling the circulation of air therethrough, a solenoid for controlling the position of said damper, and means dependent on the temperature of said cooling unit for starting and stopping said refrigerant-circulating means to maintain a predetermined range of temperature 01' said cooling unit during normal operation, said temperaturedependent means energizing said solenoid to move said damper to an open position for increasing the circulation of air each time the refrigerant-circulating means is started whereby said damper occupies an open position at all times that said refrigerant-circulating means is oper= ating, said damper being gravity-biased to a closed position whereby said damper moves to a closed position to reduce circulation of air when said solenoid is deenergized, said temperaturedependent means also being effective to deenergize said solenoid each time said refrigerant-circulating means is stopped whereby said damper occupies a closed position at all times that said refrigerant-circulating means is idle.

4. In a refrigerator including a cooling unit and refrigerant-circulating means, means including a liner for defining a food storage compartment. the cooling unit being disposed in the upper portion of said compartment, a bafile spaced from the bottom of said cooling unit and extending across the width of said compartment, said baffle extending substantially the entire depth of said compartment and being spaced from the back of said liner to provide a passage for air circulating within said compartment and over said cooling unit, a damper hinged adjacent said back of said liner and biased by gravity to engage said baffle for closing said passage to restrict air circulation within said compartment, a solenoid for lifting said damper out of engagement with said bafile to open said passage, and means responsive to the temperature of said cooling unit for starting and stopping said refrigerant-circulating means to maintain a predetermined range of temperature of said cooling unit during normal operation, said temperature-responsive means energizing said solenoid to open said passage each time the refrigerant-circulating means is started whereby said passage is open at all times that said refrigerant-circulating means is operating, said temperature-responsive means deenergizing said solenoid to allow said damper to close said passage by gravity each time said refrigerant-circulating means is stopped to stop operation thereof whereby said passage is closed at all games that said refrigerant-circulating means is ALFRED G. J ANOS.

REFERENCES CITED The following references are of record in the file or this patent:

UNITED STATES PATENTS Number Name Date 2,042,384 Bird et a1. May 26, 1936 2,126,285 Schaaf Aug. 9, 1938 2,133,958 Kalischer Oct. 25, 1938 2,244,892 Newton June 10, 1941 2,480,617 Tobey Aug. 30, 1949 

